UVA - 10201 Adventures in Moving - Part IV

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;

const int MAXN=110;

int main(){
int distance,dp[MAXN][MAXN*2],T,stations,station[MAXN][2];
char input[30];
scanf("%d",&T);
while(T--){
stations=0;
memset(dp,0X7F,MAXN*MAXN*8);
int MAX=dp[0][0],ans=MAX;
scanf("%d",&distance);
getchar();
while(gets(input)&&input[0]!='\0'){
sscanf(input,"%d %d",&station[stations][0],&station[stations][1]);
if(station[stations][0]>distance)
continue;
if(station[stations][0]==station[stations-1][0]&&station[stations][1]>station[stations-1][1])
stations--;
else if(station[stations][0]==station[stations-1][0]&&station[stations][1]<station[stations-1][1]){
stations--;
station[stations][1]=station[stations+1][1];
}
stations++;
}
/*for(int i=0;i<stations;i++)
printf("%d %d\n",station[i][0],station[i][1]);
puts("");
*/
if(stations==0){
if(distance>0)
printf("Impossible\n");
else
printf("0\n");
continue;
}
if(station[0][0]>100){
printf("Impossible\n");
continue;
}
for(int i=1;i<stations;i++){
if(station[i][0]-station[i-1][0]>200){
printf("Impossible\n");
goto next;
}
}
if(station[stations-1][0]+100<distance){
printf("Impossible\n");
continue;
}
for(int i=200;i>=0;i--){
if(i<100-station[0][0])
break;
dp[0][i]=(i-100+station[0][0])*station[0][1];
}
for(int i=1;i<stations;i++){
for(int j=200;j>=0;j--){
for(int t=station[i][0]-station[i-1][0];t<=200;t++){
if((j-(t-station[i][0]+station[i-1][0]))<0)
break;
dp[i][j]=min(dp[i][j],dp[i-1][t]+(j-(t-station[i][0]+station[i-1][0]))*station[i][1]);
}
}
}

//printf("%d",ans);
for(int i=0;i<=200;i++){
if(i-(distance-station[stations-1][0])>=100)
ans=min(ans,dp[stations-1][i]);
}
if(ans==MAX)
printf("Impossible\n");
else
printf("%d\n",ans);
next:{}
if(T)
printf("\n");
}
return 0;
}